[
https://issues.apache.org/jira/browse/PDFBOX-4900?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17156233#comment-17156233
]
Tilman Hausherr commented on PDFBOX-4900:
-----------------------------------------
positive feedback was given by mail.
This solution is not a perfect one, for example it ignores images, and
colorspaces made of other colorspaces. This opens a real can of worms (see also
my first comment), despite that it is a rather obscure feature. I ran a
software to find examples in our corpus, and the cases I found always had a
"backup", i.e. the actual color value was used so that it came out white. One
can only notice the difference by using ARGB feature when rendering, now such
areas are transparent instead of white.
What's also missing is "All". This one I didn't understand.
So I'm setting this to resolved anyway; if anyone hits an example where it is
needed, please create a follow-up issue.
> PDFBox Rendering of PDF Page incorrect when using the special None Named
> Separation
> -----------------------------------------------------------------------------------
>
> Key: PDFBOX-4900
> URL: https://issues.apache.org/jira/browse/PDFBOX-4900
> Project: PDFBox
> Issue Type: Bug
> Components: Rendering
> Affects Versions: 2.0.19
> Environment: Windows Linux
> Reporter: Andrew Daykin
> Assignee: Tilman Hausherr
> Priority: Major
> Fix For: 2.0.21, 3.0.0 PDFBox
>
> Attachments: ImageMagic_TwoCircles_NS-None.png,
> PDFBox_TwoCircles_NS-None.pdf-1.png, TwoCircles_NS-None.pdf, TwoCircles_NS.pdf
>
> Original Estimate: 336h
> Remaining Estimate: 336h
>
> Setting a Named Separation to "None" is a way of creating an ink should be
> ignored by the rendering application. This doesn't happen in PDFBox as it
> appears to use the CMYK representation when displaying the PDF in the
> debugger and when it creates a rendered png file.
> i.e.
> BufferedImage bim = pdfRenderer.renderImageWithDPI(page, 300, ImageType.RGB);
>
> Other applications (Acrobat, ImageMagick etc.) render the output correctly.
>
> The attached PDF FIle illustrate this.
>
> TwoCircles_NS.pdf was created in Adobe Illustrator and saved as PDF without
> compression. It uses a couple of named separations NS_1 and NS_2.
>
> TwoCircles_NS-None.pdf is the same PDF content but the names of the name
> separations have both been set to "None" - This was done in a HexEditor but
> in practice it is done via PDFBox.
>
> PDFBox_TwoCircles_NS-None.pdf-1.png is the result of the PDFBox Render to PNG
> which doesn't appear to follow the PDF Spec. and the definition of None when
> used as a named separation.
>
> ImageMagic_TwoCircles_NS-none.png is the output from "magick convert -density
> 150" which appears to be correct/gives the desired result.
>
>
>
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@pdfbox.apache.org
For additional commands, e-mail: dev-h...@pdfbox.apache.org
